1. Field of the Invention
The invention relates to a non-volatile memory apparatus and an erasing method thereof. Particularly, the invention relates to a non-volatile memory apparatus capable of erasing at least one of memory sectors which disposed in a same well.
2. Description of Related Art
In prior art, when an erasing operation is operated on a flash memory apparatus, all the memory sectors disposed in a same well must be erased simultaneously. Referring to FIG. 1A, a flash memory apparatus 110 includes memory sector 0 MS0 and a memory sector 1 MS1, a sector 0 selector SSD0 and a sector 1 selector SSD1. The sector 0 selector SSD0 corresponds to the memory sector 0 MS0, and the sector 1 selector SSD1 corresponds to the memory sector 1 MS1. The memory sector 0 MS0 and the memory sector 1 MS1 are respectively disposed in different wells. The sector 0 selector SSD0 is disposed between the memory sector 0 MS0 and the memory sector 1 MS1 for separating the memory sector 0 MS0 and the memory sector 1 MS1. When an erasing operation is operated on the flash memory apparatus 110, at least one of the memory sector 0 MS0 and the memory sector 1 MS1 is selected for erasing, and all of the memory cells in the selected memory sector are erased simultaneously. That is, in prior art, it is impossible to erase a part of memory cells of the memory sector 0 MS0 or the memory sector 1 MS1, and a small size memory sector erasing capability can not be achieved in the flash memory apparatus 100.
On the other hand, for the small size memory sector erasing purpose, another prior art flash memory apparatus 120 is shown as FIG. 1B. The memory sector 0 MS0 in FIG. 1A can be divided into a memory sector 01 MS01 and a memory sector 02 MS02 in FIG. 1B, and the memory sector 1 MS1 in FIG. 1A can be divided into a memory sector 11 MS11 and a memory sector 12 MS12 in FIG. 1B. Furthermore, the memory sectors MS01˜MS12 can be respectively disposed in four different wells, and two sector selectors SSD01 and SSD02 and two sector selectors SSD11 and SSD12 are necessary. The sector 01 selector SSD01 corresponds to the memory sector 01 MS01, the sector 02 selector SSD02 corresponds to the memory sector 02 MS02, the sector 11 selector SSD11 corresponds to the memory sector 11 MS11, and the sector 12 selector SSD12 corresponds to the memory sector 12 MS12. That is, the number of wells and the sector selecting devices are increased in the flash memory apparatus 120, and the chip size of the flash memory apparatus 120 is increased.